Numerical Simulation Of Solid-Fluid Two Phase Flow Characteristics On Doublet Type Sand Collector

With the obliteration of lakes and rivers getting more widely and seriously, it becomes the key problem that how to solve the obliteration effectively. In traditional ways, the efficiency of the cutter suction dredger or the only suction dredger is fairly low. Professor Nozaki in Kagoshima University designed a new doublet type sand collection and separation system. With an injection pipe injecting water into the sand settled layer, sands are fluidized widely, then the two phase flow will be transported up through the suction pipe. This method of dredging is convenient and efficiency to be able to widely used in actual environment. This paper is based on the simplified doublet sand collector model, using Gambit to mesh the model and make simulations with Fluent, to obtain the basic characteristics of two-phase flow in it. Euler model and turbulence model of the two-phase flow are built though related theories of fluid dynamics of multiphase systems. An interphase drag model is also chosen during to actual conditions. It is simulated that how structural and environment parameters affect the work efficiency of the sand collector, some optimal values under some certain conditions are obtained. Finally, a qualitative wear analysis of a common 90°elbow in piping system is conducted. It is revealed of basic laws of wear distribution under different conditions of flow velocity, sand concentration and particle diameter, so that some advices can be given to decrease wear of pipes and extend piping system's life.